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Kuala Selangor is located in Sungai Selangor estuary in the west coast of Peninsular Malaysia. Kuala Selangor coastal area is susceptible to pollution load as a lot of industrial and human activities are located in the west coast of Peninsular Malaysia and along Sungai Selangor. Surface sediment was taken from 14 points at two locations in southern Kuala Selangor that are in ‘Pantai Remis’ and ‘Pantai Jeram’. This study focused on radioactivity level of naturally occurring radionuclide (mainly 226Ra, 228Ra and 40K) in surface sediment using gamma-ray spectrometry with a high-purity germanium (HPGe) detector. For 40K, the presence of this was measured directly via its 1460 keV energy peak. For 226Ra (of the 238U) and 228Ra (of the 232Th) the γ-ray lines 609.3 keV (214Bi) and 911.1 keV (228Ac) were used. The concentration of 226Ra, 228Ra and 40K in samples obtained from Pantai Remis coastal area ranged between 42.9±1.4-60.0±1.6 (mean 47.6±1.5) Bq/kg, 61.9±2.8-79.3±2.9 (mean 69.5±2.7) Bq/kg and 324.5±10.6-455.8±13.2 (mean 422.2±12.2) Bq/kg, respectively. Meanwhile, the concentration of 226Ra, 228Ra and 40K in samples obtained from Pantai Jeram coastal area ranged between 45.1±1.6-50.4±1.5 (mean 47.2±1.6) Bq/kg, 62.5±2.8-75.9±3.0 (mean 69.2±2.9) Bq/kg and 338.7±10.7-490.6±14.0 (mean 428.2±12.4) Bq/kg, respectively. The mean external hazard index due to these radionuclides is 0.484 for ‘Pantai Remis’ and ‘Pantai Jeram’ (less than unity). Thus, it is expected that no radiation hazard attributed to the radiation from the study radionuclides will be experience by people in the areas.

Two sediment cores in Kuala Selangor estuary and Pantai Remis coastal area were obtained using gravity corer and then were analyzed using Alpha Spectrometry System. In order to estimate the sedimentation rate in the area, 210Pb dating technique and Constant Rate & Supply (CRS) model were used. From the study, the vertical profile of 210Pb shows a decreasing trend with depth and finally achieving a constant level. Based on the vertical profile of 210Pb, activity of excess 210Pb was obtained and was used to determine the sedimentation rate in the study area. Pantai Remis coastal area shows high sedimentation rate than Kuala Selangor estuary which may due to high sediment input in the area. Besides, the differences in sedimentation rate might be attributed to highly variable sedimentary and hydrodynamic conditions in the estuary and coastal area.

Many articles have been published on ink analysis to assist Forensic Document Examiner (FDE) in examining questioned documents. Ink analysis encountered about 45% of ballpoint and 24% of gel pen in forensic cases. Typically, ink samples found on the documents are limited to small quantities, requiring non-destructive techniques to preserve the evidence. Previous studies on ink analysis cover about 80% of spectroscopy techniques, including the Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR). FDE prefers ATR-FTIR to retain the legibility of evidence since ATR-FTIR is known as non-destructive, fast, reliable, and precise instrumentation. Various modifications and developments to this technique have been published. Therefore, this work reviews the trend of analysis performed on samples of the document and evaluates the current approaches to the capacity of using ATR-FTIR on such samples. Remarks on the comparison studies are also included.